If you get an external with backup software on the drive, simply format it before use and it will remove all the software. Personally I prefer eSATA drives as they are much faster than USB 3.0 plus they have many advantages over USB. I personally prefer to use an external dock to connect to my computers. Any external drive will fit in them and can be changed out in less than 1 minute. They are very simple and quite versatile. The one I use primarially is the thermaltake Black X
. It works on USB 2.0 as well as eSATA and they make models for USB 3.0. If you prefer portable ones, I have 2 Seagate FreeAgent Go Flex drives, that I have had for about 2 years and both work well. They come with backup software already installed, which, in my opinion, is useless. I simply formatted them and the software is gone. They come with USB 2.0 cables, but USB 3.0, firewire, or Powered esata cables are available. Many now come with USB 3.0 standard.